: Physics of lifting the front wheels, how much hp is needed?



ocjmakaveli
02-25-06, 03:44 PM
I was just wondering as seen in a few movies and online some cars have enough torque/hp to make the front wheels lift off the ground some from a few inches to even a few feet.

I was just wondering on our 94-96 fleetwoods is this even remotely possible?

Would it require a really hard suspension? Around how much hp/tq to achieve at least 2" of front wheel hop?

I think I've seen an impala ss lift up the front wheels before a few inches but I lost the page and what mods it had etc.

It would require a posi and really good tires to achieve such lift or else the wheels will just spin like crazy I assume.

N0DIH
02-25-06, 06:10 PM
Possible, oh yes. I come from the Pontiac camp, 455's LOVE to do this. Even in 5000# battlewagons. I have seen many of the B body Pontiacs with 455's and noses in the air with 3.08 gears-3.55 gears.

Follow closely Jim Hand's 71 GTO Wagon. He weighs in at 4000 lbs, runs 3.55's, and catches air on every pass. He has a 473 CID (60 over 455) with a 4.25" stroke crank (stock is 4.21, this is a new CAST crank), and has run a best of 11.32. He has been pulling front wheels since he was at low 12's on factory parts (note, I didn't say, as factory delivered, but WITH 90% or more of factory off the shelf, in production vehicles). Note Jim does not rev past 5500.

Read the first combo:
http://www.pontiacstreetperformance.com/psp/rebuild455jh99.html

Then the current combo:
http://www.pontiacstreetperformance.com/psp/rebuild455jh00.html

Jim is very meticulous with his mods and combination. He has a book out, I highly recommend its reading.

He ran a solid 12.2 1/4" with 4000 lbs with a 455 and a 068 cam and 3.23's for many years. Please note an 068 cam (the last 3 numbers of the GM P/N) is the 400 stick shift cam. About the same cam specs as a GM HOT cam with .410 lift on 1.5 rockers. This provided excellent drivability and power. The 041 cam, the Ram Air IV cam, .470 lift, 308/320 duration, 231/240 @ 0.050, was too rough and poor drivability w/o Rhodes lifters.

As for suspension, Jim's has leaf springs, but for the ultimate in B/D traction, talk to Dick Miller, he can make a lawn mower hook up....

Lifting fronts on a small block car is tough due to the lack of low end power, so short gears are a necessity, the big inch motors have this in abundance, so they can do it with 3.08's to 3.55's.

96Fleetwood
02-26-06, 01:53 AM
I have seen low 10 second Impala SS vehicles lift the front wheels. I do not know of a low 10 second Fleetwood.. yet...

Now getting the rear to break loose from a standing start without TC is very feasible :thumbsup:

90Brougham350
02-26-06, 03:35 AM
From the Chevyhiperformance boards:

1. A bunch of power under the hood.
2. Some fairly deep rear cogs with a spool or well built posi unit.
3. A driveline which can stand a tremendous "jolt" of energy, and can apply it to the ground.
4. Wide, sticky tires which will provide traction rather than squeal.
5. Plus about a dozen other requirements.
Oh, BTW, while it may look cool to raise the skinnies it's not what you want to do at the track - it's wasted energy, motion and time. Just ask any racer.

I think it'd be bad-ass to see a Fleetwood raise the tires! It'd be the ultimate sleeper car, kind of like that station wagon that was in a video in the lounge!

pimpin88
02-26-06, 12:33 PM
i know of one 10 second fleetwood. i posted a picture of him a while ago. he has transplanted a 455 into his. although i dont recall if the front wheels came off the ground.

here are the two pics of his car.

oh, and the third one actually has the wheels off the ground :histeric: :histeric: :histeric: :histeric:

pimpin88
02-26-06, 12:34 PM
oh, btw, that third one was because the guy floored it and the front of his car came up and ended up on top of the other car. jk.

someone else had posted that a while ago and i love that picture.

96Fleetwood
02-26-06, 01:34 PM
Ah, the good old 455 Rocket. What an engine!

davesdeville
02-26-06, 06:43 PM
In a smallblock powered nose-heavy car you'd need some very high (numerically) gears, a good posi, wide drag radials at the least, probably 600ft.lbs. to the wheels. Easiest way would probably be a big block transplant, a strong blown 500 would do nicely.

N0DIH
02-27-06, 01:20 AM
You know, my 3 ton floor jack will get the front wheels in the air too....

N0DIH
02-27-06, 01:56 AM
For a Sloblock, this is correct, for a healthy big in BOP motor, I would recommend:

1. 440 CID or 7.3L or larger, bigger is better.... :)
2. 1 3/4" headers, 4-2-1 collectors, 2.5"-3" duals. 2.5" is good for low 11's, so don't go crazy here.
3. 3.08-3.55 gears, good posi/locker. 8.5" ring gear or larger.
4. 275 60 R15 Drag Radials or slicks.
5. Cam around 231/240 duration, Rhodes lifters (mandatory)
6. Dick Miller rear control arms (adjustable and strong)
7. Dual plane intake, Edelbrock rpm style if available. Aluminum to lose weight.
8. Compression 9.5:1 to 10:1.
9. Edelbrock AFB 750 cfm carb, Q-Jet or 750 Holley
10. Prefer aluminum heads if possible, but iron heads are fine if ported properly by competent porter. Do not port like crazy, keep velocity high, this is key. Aluminum to lose weight.
11. Blown front shocks are helpful for weight transfer

This should get you pretty close in seeing air under the front tires!!


From the Chevyhiperformance boards:

1. A bunch of power under the hood.
2. Some fairly deep rear cogs with a spool or well built posi unit.
3. A driveline which can stand a tremendous "jolt" of energy, and can apply it to the ground.
4. Wide, sticky tires which will provide traction rather than squeal.
5. Plus about a dozen other requirements.
Oh, BTW, while it may look cool to raise the skinnies it's not what you want to do at the track - it's wasted energy, motion and time. Just ask any racer.

I think it'd be bad-ass to see a Fleetwood raise the tires! It'd be the ultimate sleeper car, kind of like that station wagon that was in a video in the lounge!

ocjmakaveli
02-27-06, 03:35 AM
The picture is just incredible.

I guess i'm going to look and see who has been able to lift the front wheels up on launch for the impala ss the fleetwoods should be almost the same.

I would like to see it happen but just because it would look SO NICE not really because it'll be better or safer overall but I think it would feel nice too and the look of your opponents face.......Priceless!

To me the ultimate car is a classy outside with a silent exhaust but enormous speed. I love sleeper cars.

If luck permits and all goes well I will definitely be swapping out the motor in the future for no less than a 450hp/400 tq at the rear wheels. I want something driveable though not just track friendly.

This is just one of those things if it becomes plausible I'll go for it but I'll have to do more research. A 7 liter seems a little too big :worship: but if that's what it takes then it'll have to happen.

Thanks guys

BCs71
02-27-06, 11:20 AM
Now getting the rear to break loose from a standing start without TC is very feasible :thumbsup:

I agree! :bouncy:

See it here!
http://www.badbodies.com/caddy4.wmv

N0DIH
02-27-06, 01:25 PM
Believe me, I have a 455 in the basement that I really have been considering dropping in my Cad. With the EFI of course!! But, do I put an Opti on the Pontiac V8?? AAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHHHH

96Fleetwood
02-27-06, 02:59 PM
This weekend I had the opportunity to ride in a 509 cubic inch Impala SS... the car hits low 10s full motor and does get the front wheels in the air. A 509/4L80 swap in the Fleetwood... hmm....

ocjmakaveli
02-27-06, 03:51 PM
This weekend I had the opportunity to ride in a 509 cubic inch Impala SS... the car hits low 10s full motor and does get the front wheels in the air. A 509/4L80 swap in the Fleetwood... hmm....

WOW do you know if he visits the impala forums or his nickname online?

That would be incredible 500 cubic inches of raw power I'd like to know how hard of a swap it is and how much $ is involved for new or semi-new parts.

How much room is there in the engine compartment with a 500 cubic inch engine in there? I didn't think that size would fit in our caddys.

I've had a plan of spending roughly $10,000-$15,000 for new engine tranny and driveline parts(posi included). To me it's far better than buying a sports car in which I'll easily pay $5,000+ in insurance for it every year. If this would fit my budget then I might even do it by the end of the year hopefully.

96Fleetwood
02-27-06, 03:54 PM
Nope, sorry.. this guy is not internet savy. However there are several Impala guys on the forums running 500 cubes.

Bill D (BIG KAHUNA ****e (http://impalassforum.com/cgi-bin/ultimatebb.cgi?ubb=get_profile;u=00004471)) has a 1994 with a 502 in it :thumbsup:

N0DIH
02-27-06, 04:27 PM
In a few years I might look that way. Pick up a good 2WD 96-99 Sururban/Chevy truck with a 454 and yank it, drop in in the LT1 or a Vortec 350 and send it away. And you have a good torquey Vortec 454 w/4L80E w/PCM. Do some cam revisions, PCM tuning and you have a great runner. Then grab a 496 stroker crank and drop it in and you have a long stroke 454, aka, 496....

davesdeville
02-28-06, 03:20 AM
The B&D bodys chassis is quite similar to the 77-92 Fleetwoods. Meaning it wouldn't be too incredibly much work for a 500ci Caddy motor. For cheapness it would be the way to go: do a cam, ported stock intake manifold, headers with duals, and a 250 shot. It should live for quite awhile and should do around 500hp to the wheels. And you'd need some good drag radials to put well over 500ft.lbs. to the ground... Including the cost of a running core that would be around $1k into the motor. Add $1.5k for forged internals and a good shaft rocker setup and it would live for a very long time, plus you could run an even bigger cam if you wanted to.

Katshot
02-28-06, 06:53 AM
I agree! :bouncy:

See it here!
http://www.badbodies.com/caddy4.wmv

Got THAT covered! ;)

BCs71
02-28-06, 01:20 PM
Got THAT covered! ;)
Got any video to accompany that picture?? Looks like a doosey. :thumbsup:

The attached picture is what's left after a peel-out in the Caddy. Notice the really long one-wheel peel........:rolleyes:



http://hometown.aol.com/bcndahous/images/capricetiremarks.jpg

Katshot
02-28-06, 02:36 PM
No, never done video of it. Wouldn't have a clue how to post it anyway.

N0DIH
02-28-06, 07:34 PM
2.93's or 3.42's?? I should do one of those before I pull the snow tires off for the last time, as they are worn out. Anyone in Chicagoland wanna borrow one or two to smoke off??
Got any video to accompany that picture?? Looks like a doosey. :thumbsup:

The attached picture is what's left after a peel-out in the Caddy. Notice the really long one-wheel peel........:rolleyes:



http://hometown.aol.com/bcndahous/images/capricetiremarks.jpg

kdrolt
03-01-06, 10:35 AM
Of course you could replace the rear springs with temporary blocks and then add a lot of weight to the trunk, to move the vehicle c.g. aftward. If you move it far enough back, then the stock engine can lift the front end. The front wheels will lift from the pavement, but the car will be reaaaaaly slooooow (from the extra weight you added).

The altered wheelbase drag cars from the 60s used the same concept to maxmize the loading on the rear tires, but they did it by moving the rear axle forward rather than in adding weight into the trunk.

And OBTW, it's not so much hp needed in a true physics sense to lift the front wheels --- it's the combination of the engine delivered torque plus the gear multipliers of the trans + rear end ring/pinion. A free-body diagram of the car (using forces and moments) is the starting point for this, where you assume that the car accelerates enough to have no force between the front wheels and the road -- so the unknown that you solve for is the acceleration needed which will, in turn, reduce to the torque needed at the rear wheels.

FWIW.

ocjmakaveli
03-02-06, 01:28 PM
are these statements true?

http://www.geocities.com/MotorCity/Pit/9364/guide/Why.htm

btw the page mentions a 540 stroker with 600hp and 700 ft. lbs of torque how much would that cost?

That would truely be amazing.:worship: :worship: :worship: :worship: :worship: :worship: :worship:

BCs71
03-03-06, 07:03 PM
2.93's or 3.42's?? I should do one of those before I pull the snow tires off for the last time, as they are worn out. Anyone in Chicagoland wanna borrow one or two to smoke off??

In that picture my Caprice had the stock 2.93s and 28" tall tires. :eek:
Bone stock vehicle!

N0DIH
03-03-06, 07:15 PM
What about the FW?

davesdeville
03-05-06, 06:34 AM
are these statements true?

http://www.geocities.com/MotorCity/Pit/9364/guide/Why.htm

btw the page mentions a 540 stroker with 600hp and 700 ft. lbs of torque how much would that cost?

That would truely be amazing.:worship: :worship: :worship: :worship: :worship: :worship: :worship:

I doubt I'd bother spending the money on stroking it. But at those power levels you're looking at a LOT of money or forced induction. I'd figure $4-6k for a blown, forged internal 500 making that kind of power.

BCs71
03-06-06, 03:44 PM
What about the FW?

It's a Brougham so it had a one-legger from the factory with 2.93 gears. That's what it had in that peel-out video.

After that video made (last spring, actually) I had a set of 3.42s installed with a posi differential. I haven't replicated that video yet..... in fact I haven't really driven the Fleetwood much at all. It's been tucked away all winter in the garage and before that the body shop had it for 6 weeks. :thehand: And before that it was all keyed up so I didn't like driving it too much since it was kinda depressing.

So hopefully this spring/summer I'll make it my commuter or something to catch up on mileage. :bouncy: